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Furnaces 101

Furnaces 101

If your furnace is more than 10 years old, it may almost be time to think about replacing it or doing some furnace repairs. Depending on what furnace type and size you need, it could cost you $2,000 to $15,000 to purchase a new one. We have some general furnace 101 information to help you decide what’s best for you.

Replacing Your Furnace

Thinking of replacing your furnace? There are a few questions you’ll need to answer first:

  • How big is your house? The bigger the house, the bigger furnace you’ll need.
  • What’s your home like? A home with an open floorplan, wood siding and many older windows will use a larger furnace than a brick home with smaller rooms and newer windows would.
  • Where do you live? A home in the more southern or western states need less heating power than if you live in the north or east.
  • What’s a BTU and why does it matter? BTU = British thermal units, and one BTU is how much energy is used to raise the temperature of one pound of water up one degree Fahrenheit. The bigger the home, the more BTUs you’ll need.  
  • What’s an AFUE percentage and why does it matter? AFUE = annual fuel utilization efficiency. A good furnace will have a rating of at least 80% or higher.

Fixing Your Furnace

If you don’t have thousands to spend on a new furnace (And honestly, who does?!) Here are a few furnace parts that may need replacing:

  • Thermostat
    If your furnace is over- or under-heating, it may not be the furnace but the thermostat instead. First check the wiring going to the thermostat and the thermostat itself to ensure it’s connected correctly and debris-free. If you have a digital thermostat, make sure it doesn’t need a new battery. If you don’t have a digital thermostat, it’s way more energy efficient to have one – so replace it sooner rather than later.
  • Air filter
    Is your home dustier than usual? Or is your furnace not heating like it used to? Then a dirty air filter could be the culprit. Good news, this is one of the most easy and affordable furnace fixes out there! Just make sure you have the right size and type of filter for your furnace.
  • Flame sensor
    Sometimes a faulty or dirty flame sensor will cause your gas furnace to keep shutting off. The flame sensor is there to let the furnace system know there’s a flame if the gas valve is open. The sensor can get carbon buildup, which can stop it from working correctly. If you’ve cleaned the flame sensor and your furnace still shuts off frequently, then chances are it’s time to replace it.
  • Furnace igniter
    Your furnace igniter may be on the fritz if your furnace isn’t turning on when it’s supposed to or there’s no heat whatsoever when it is running. An ignitor is on a gas furnace and automatically lights the pilot assembly or main burners. If your furnace has a hot surface ignition, it uses an ignitor. If the ignitor is cracked, it’s time to replace it.

Ever wonder how a furnace works?

If you need additional assistance, be sure visit our Furnace Repair Help. And don’t forget that Repair Clinic has millions of heating and cooling parts available for same-day shipping and we offer a 365 return policy guarantee.




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